Macro image capture lens feeding devices have been developed (see Patent Document 1) for use in conventional optical equipment using CCDs (Charge Coupled Devices) or CMOS (Complementary Metal Oxide Semiconductor) devices as image capture elements, with the aim of for example reducing the number of parts, decreasing the equipment size, reducing the amount of rotation operation to perform image capture mode switching operations, and improve operability. Such macro image capture lens feeding devices comprise a holder into which is incorporated an image capture element, an elastic member to prevent shaking of the image capture lens, a feeding ring, a lens barrel incorporating a lens group which comprises the image capture lens, and an operation knob.
In the macro image capture lens feeding device, switching between the normal image capture and the macro image capture modes is performed by advance and retreat movement of the feeding ring by means of screwing of a multiple-thread male screw of a feeding ring and a multiple-thread female screw of the holder, by rotating the feeding ring integrally with the operation knob. Focus adjustment of the image capture lens incorporated into the lens barrel is performed using the focus adjustment female screw of the feeding ring and the focus adjustment male screw of the lens barrel.
As another example, a compact and inexpensive lens adjustment device with a simple configuration has been disclosed, comprising a lens adjustment mechanism which performs image capture lens focus adjustment and image capture mode switching (see Patent Document 2). This lens adjustment device has cam portions at the fixed lens barrel and at the lens frame, and comprises an adjustment ring having at one end a cam portion joined with the cam portion of the lens frame, and having at the other end a cam portion joined with the cam portion of the fixed lens barrel; a function is comprised such that, by rotating an adjustment lever, the lens frame moves forward and backward along the optical axis, and switching between normal image capture mode and macro image capture mode is possible.
Further, a focusing adjustment mechanism, which enables focusing adjustment during assembly without causing lens optical axis shifts, has been disclosed (see Patent Document 3) as an example of formation of a lens feeding mechanism which utilizes a cam mechanism similar to that of the above-described lens adjustment device. By means of this focusing adjustment mechanism, a focusing adjustment function is effected by rotating the feeding member at the time of focusing adjustment to adjust the position of the member. Hence even when the feeding member is rotated for focusing adjustment, the lens moves along the optical axis according to the rotation amount, so that optical axis shifts due to eccentricity and similar do not occur.
Patent Document 1: Japanese Unexamined Patent Application Publication No. 2003-337279
Patent Document 2: Japanese Unexamined Patent Application Publication No. 10-170809
Patent Document 3: Japanese Unexamined Utility-Model Application Publication No. 03-33421